semiconductors:
3x TL072

resistors
12X 100k

capacitors
5x 0.1uf ceramic

potentiometers
10x b100k alpha 9mm vertical style

switch
2x 0.1" spacing spdt on on toggle such as mouser 108-0048-evx

10x "earthenvar" type jacks
kobikonn or thonkiconn will work but you need to wire the ground leads to somewhere else on the board.

female header strips
(you need the same, but male for the duofonik if you want to use it with this)

3x1
2x1
15x1
17x1

thats it!